Blow-out preventer



n Dec. 6, 1938. o. c. sNELL BLOW- OUT PREVENTER Filed March 12, 1955 2 Sheets-Sheet 1l y 37 "r/ v f /8 /s AWA L /4 22 s4 so al 35 Hl l Dec.6,193s. Ofc, SNELL k l 2,139,525

BLOW- OIUT PREVENTER Filed March l2, 1935 2 Sheets-Sheet 2 F f 4g 5 o A P5' 4/ gg; lsf 44* `44 IIL Fn i a' LILI LLI :jme/whom Patented Dec. 6, 1938 PATENT OFFICE BLOW-OUT PREYENTER Owens C. Snell, Houston, Tex., assignor of fortyl per cent to R. R.. Ratliff, Houston, Tex.

Application March 12, 1935, lSerial No. 10,640

2 Claims.

This invention relates to a blowout preventer.

An object of the invention is to provideva blowout preventer to be secured to the top of a casing in a well bore, and adapted to be` actuated by an operating uid, and/or by the iiuid issuing under pressure from the well, into position to close the space between said casing and an inner pipe therein, in case a blowout occurs.

Another object of the invention is to provide a blowout preventer arranged to be actuated by an operating uid under pressure, into active position to close said space and adapted to be actuated by suction into inactive position.

A further object is to provide a blowout preventer of the character described embodying packing means arranged to form a Huid-tight joint about the kelly-joint of the drill stem while drilling in the presence of a threatened blowout, and also embodying means for closing the space between the outer pipe or casing and the drill stem beneath the kelly in case the threatened blowout occurs.

A still further feature of the invention resides in the provision of a blowout preventer embodying a housing provided with cylinders with rams in the cylinders having packing means assembled therewith in a novel manner with means for applying an operating fluid under pressure to and relieving the same from the cylinders to move the rams and packing into active or inactive position, provision being made for utilizing the gas pressure from the Well to assist in moving and maintaining the rams and packing in said active position to close the space between the outer pipe and the drill stem or other inner pipe.

The invention also comprehends aV construction whereby the expulsion of the drill stem from the well by internal pressure will be prevented.

With the above and other objects in view, the invention has particular relation to certain novel features of construction, operation, and arrangement of parts, an example of which is given in this specication, and illustrated in the accompanying drawings, wherein:

Figure 1 shows a vertical sectional view of the apparatus, showing the kelly packer removed.

Figure 2 shows a cross-sectional View taken on the line 2 2 of Figure 1.

Figure 3 shows a fragmentary side view of a plunger with the packing mounted thereon.

Figure 4 shows a side view, partly in section, of the apparatus, showing the kelly packer thereon.

Figure 5 shows a cross-sectional view taken on the line 5-5 of Figure 4, and

Figure 6 shows a cross-.sectional view taken on the line 6-6 of Figure 4.

In the drawings, the numeral I designates the housing, which kis adapted to be connected, in any suitable manner, to .the upper end of the well casing 2. The housing contains the upwardly converging cylinders 3, 3, in which the rams 4, 4, are mounted.

At their upper ends, the rams have the eX- ternal vertical dove-tailed grooves 6, 6, therein, and tted through the housing walls, are the externally threaded bolts 1, 1, whose inner ends are tted into and are shaped to conform to the contour of the grooves 6. These bolts are locked in place by the clamp-nuts 8, 8, which are screwed on the outer end thereof. The rams are thereby held against turning in the cylinders, but are permitted to move longitudinally therein into active or inactive position.

The lower ends of the cylinders have the heads 9, 9, bolted or otherwise secured thereto.

Packing, as I0, is secured to the lower ends of the rams. Each packing contains the reinforcing plate II embedded therein, and has a clamp plate I2 abutting the outer end thereof. The packing assembly is secured to the outer end of each ram by the set-bolts I3.

On the upper ends of the rams, are the halfround complemental packing assemblies I4, I4,

each composed of the upper and lower arcuate plates I5, I 6, and the similarly shaped packing I'I, Il, between said upper and lower plates. These assemblies are maintained in assembled relation by the clamp-bolts I 8, I8. The upper ends of the rams have the radial dove-tailed grooves I9, I9, and depending from the lower plates I6, are the dove-tailed tenons 20, 20, which are located in the corresponding grooves I9. The packing assemblies I4 are tapered on their outer sides to conform to the taper of the upper Aends of the cylinders 3, 3, and on their inner sides, are shaped to fit closely about the drill stem or other inner pipe 2l, when the packing assemblies are in active position.

'I'he inner sides of the upper ends of the rams 4 are correspondingly bevelled to present the opposing flat faces, 22, 22, which have the vertical complemental triangular grooves 23, 23, to provide a passageway for the inner pipe. This passageway, at its lower end, is enlarged, as at 24, to provide a seat for the coupling 25 of the inner pipe, and to form the inside shoulders 26, 26, against which the upper end of said coupling may abut when the rams are in active position to prevent the inner pipe from being expelled by internal pressure from the well.

Each head 9 has a passageway 21 in communication with the interior of the casing 2 and valve seats 28, 28, are screwed into said heads, and the passageways 21 continue through the said seats into the lower ends of the cylinders 3, and are controlled by the inwardly opening valves 29, 29.

There is a control-valve casing 39 containing a rotatable three-way valve 3|, which may be manipulated by the handle 32. Leading from the valve casing through the respective heads 9, are

the pressure lines 33, 34. Entering the valve casing from the pressure side of a suitable pump, is the pressure line 35, and leading from the valve casing 39 to the suction side of said pump, is the suction line 36. The valve 3| may be turned into the position shown in Figure 1,'and the operating iiuid such as slush, or oil, thus delivered through the line 35, and thence on through the` lines 33, 34, into cylinders 3 to force the rams 4, 4, upwardly or into active position, and as said rams are forced upwardly, the packing assemblies 4, I4, will also be forced upwardly and inwardly to closely surround the drill stem, or other inner pipe 2|. When the valve 3| is in the position stated, the suction line will be closed. The gas or liquid issuing, under pressure, from the well, will also pass through the channels 21 into said cylinders, and will assist in actuating the rams 4 into active position or in some cases may be suflicient, unassisted, to accomplish that purpose, and when the rams are in active position, the well pressure may at times be suicient to maintain them in said active position without assistance from the operating uid.

When it is desired to move the rams 4 into inactive position, the valve 3| may be turned a quarter of a turn to close the line 35,-and to communicate the suction line 36 with the lines 33, 34, and the capacity of these lines is sufficient to enable the ordinary slush pump to create sufcient suction to withdraw the rams to inactive position.

Provision is also made whereby drilling operations may be carried on safely in the presence of a threatened blowout, while the rams 4, 4, are in inactive position. For this purpose a tubular nipple, as 31, is screwed into the upper end of the housing and screwed on to the upper end of this nipple, there is a tubular head 38 having the inside downwardly converging seat 39. There is a sectional packer assembly 40 shaped to be tted into the seat 39 and composed of the upper and lower sectional metallic plates 4|, 42, and the intervening packer 43, all clamped in assembled relation by the clamp bolts 44, 44.

This packer assembly, as stated, is composed of sections which are complemental, and the assembly has the vertical axial bearing 45 polygonal in cross-section to snugly receive the kelly 46 attached to the upper end of the drill stem. There is a sectional cap 41 which is internally threaded to be screwed onto the externally threaded upper end of the head 38 to retain the packing assembly 40 in place. The sections of this cap may be secured together by means of the clamp bolts 48 so that the cap may be readily secured in place or removed.

The cap has a central circular opening 49, through which the kelly extends. While drilling in the presence of a threatened blowout, the rams 4 of the blowout preventer proper may be moved to inactive position, and the packing assembly 49 located and secured in place on the seat 39, and drilling proceeded with, the assembly 48 rotating with the kelly.

In case a blowout occurs, the rams 4, 4, may be actuated into active position, as shown in Figure 4, so as to control the well.

The drawings and description disclose what is now considered to be a preferred form of the invention by way of illustration, while the broad principle of the invention will be defined by the appended claims.

What I claim is:

l. A blowout preventer comprising a housing adapted to be connected to' an outer pipe in a well and having a passageway therethrough for an inner pipe, cylinders in the housing, rams in the cylinders movable into active and inactive positions, a packing assembly formed of complemental sections having a do-ve-tailed connection with the rams and which are radially movable into position to form a seal between the housing and inner pipe when the rams are in active position, and movable into spaced relation with the inner pipe when the rams are moved to inactive position, and means preventing the rotation of the rams in the cylinders but allowing the longitudinal movement of the rams relative to the cylinders.

2. A blowout preventer comprising a housing adapted to be connected to an outer pipe in a well and having a passageway therethrough for an inner pipe, said housing having upwardly converging cylinders, a ram in each cylinder arranged to be moved into active position and shaped to surround said inner pipe when in said active position, said rams being also movable into inactive position, means preventing the rotation of the rams in the cylinders, but allowing the rams to move into either of said positions, a packing assembly formed of complementa] sections connected to the upper ends of the respective rams and radially movable thereon into position to form a seal between the housing and inner pipe when the rams are in such active position, and movable into spaced relation with the inner pipe when the rams are moved to inactive position.

OWENS C. SNELL. 

